Razesdark

This plugin will allow all authors to have their own tweets shown on in the widget area of their posts, by adding it to their profiles. 
That way any multi-author blog can let their bloggers promote their own twitter account and not a joint account.

Author Based Twitter Widget

A Author based twitter widget, made to help multi author blogs have individual twitter widgets for their authors.

Gianluigi Filippelli

<a href="https://wordpress.org/plugins/co-authors-plus/" rel="ugc">Co-Authors Plus</a> is one of the most useful plugin for multiple authors blogs. This plugin add a widget to add users’ avatars to post also for guest authors and for posts with multiple authors. 
You can also add avatars with a shordcode [blog-post-coauthors]. 
The plugin add also a slider in order to show user’s profile. If you want change the style, you can modify blog-spoiler.css file in the plugin folder.

Co-Authors Widget

The plugin add a widget and a shortcode in order to show authors of an article. It is compatible with Co-Authors Plus.

Author Based Twitter Widget vs Co-Authors Widget